Putin should tell whether the shootdown of the plane by Russian-aligned separatists in eastern Ukraine was a mistake, she explained. The United States has said there is clear evidence the rebels shot down the plane, likely mistaking it for a Ukrainian military cargo plane.

But on Monday, Putin ignored that advice.

“Nobody should and no one has the right to use this tragedy to achieve selfish political aims,” Putin said in a video posted on the Kremlin’s website after a series of phone calls yesterday with world leaders about the crash. “Such events should unite, not divide people.”

Russia’s relations with the rest of the world are deteriorating four months after his annexation of Ukraine’s Crimea region sparked Europe’s biggest geopolitical crisis since the end of the Cold War.

The bodies of 251 people and 66 parts of human remains have been recovered and brought to refrigerated train wagons in Torez as of Monday, according to Ukraine’s state emergency service website. Rebels continue to prevent the departure of the train, Ukrainian Prime Minister Arseniy Yatsenyuk told reporters today in Kiev. The plane was shot down on July 17 killing all 298 passengers and crew.

Putin again blamed the downing of the plane on the Ukraine conflict and said that international investigators should have full access to the wreckage. Russia will “do everything it can” to seek a negotiated settlement of the Ukraine conflict, he said.

Even if it was a mistake, Feinstein said, "it's a horrendous mistake to make. It points out the futility of what's happening in the Ukraine, because there will be repercussions from this."

Host Candy Crowley pointed out that the United States keeps adding more and more sanctions on Russia over its role in Ukraine, and Putin continues to ignore them.

With the shooting of the plane and the deaths of 298 civilians from Europe and other countries, Putin may be in too deep, Crowley said, asking why would he "man up" now?

"I think the world has to rise up and say, we've had enough of this," Feinstein responded, saying that Europe has to come together, led by Germany, to impose further sanctions.

Feinstein said she opposes Republican calls to arm the Ukrainians, as they have been requesting for months, because she thinks the shooting shows that neither side needs to be in possession of such weapons.

"I'm opposed to giving this kind of equipment to anybody," she said.

At the end of the interview, Crowley posed a final question to Feinstein, saying she had time only for a yes-or-no answer: "Do you believe the U.S.-Russia relations are now at Cold War levels?"

"I believe, as you asked Senator Feinstein, that Mr. Putin is returning to a Cold War mentality," he said. "When I was over there, you could see this nationalistic pride, a sort of resurgence to regain the glory of the old days of the Soviet Empire and so we're seeing that happen with Crimea being annexed."

The comments came as European anger mounted Monday on Putin's stance and the treatment of the bodies and crash scene.

U.K. Prime Minister David Cameron said Sunday that he agreed with his French and German counterparts that Europe should be ready to impose further sanctions on Russia at a meeting of European Union foreign ministers tomorrow in Brussels. Britain wants sanctions against the entire Russian defense industry, a U.K. official said.

German Foreign Minister Frank-Walter Steinmeier said in a Twitter posting that “this is perhaps the last opportunity for Russia to show that they are seriously interested in finding a solution.” Hans-Peter Bartels, who heads the German parliament’s Defense Committee, said “time is slowly running out for Putin” and that further economic sanctions aimed at Russia are likely unless there’s a clear shift in Kremlin policy.

“There’s a build-up of extraordinary circumstantial evidence,” U.S. Secretary of State John Kerry said yesterday on NBC’s “Meet the Press” program. “We picked up the imagery of this launch. We know the trajectory. We know where it came from. We know the timing.”

Putin didn’t address the allegations in the video, saying “one can say with certainty that if the fighting hadn’t been resumed on June 28 in eastern Ukraine, this tragedy for sure wouldn’t have happened.”

Separatists had at least three Russian-made surface-to-air missile systems, known by their NATO designation SA-11 Gadfly, Ukraine state security official Vitaliy Nayda said on July 19. Three of the systems were transported back to Russia just hours after the plane was shot down, he said. Nayda displayed photos that he said showed them on the road to the Russian border.

The Gadfly, known locally as the Buk-M, is a radar-guided weapon that can locate a target at a range of 140 miles and reach altitudes as high as about 72,000 feet, according to the army-technology.com website.

Yatsenyuk told reporters today that Ukraine’s armed forces haven’t fired surface-to-air missiles, that the rocket used to down the plane came from Russia and that those who fired it had received training in Russia. He said the Netherlands and Ukraine’s international partners should lead the investigation into the crash.

The conflict in east Ukraine is raging on, even as the eyes of the world focus on the crash. There is fighting today in both Donetsk and Luhansk. Rebels shelled the downtown area of Luhansk yesterday damaging a school, a hostel and other buildings, Vladyslav Seleznyov, a military spokesman, said in comments on Facebook. The insurgents are using Grad multiple rocket systems and mortars, he said.

Ukrainian troops are holding their positions near the airports of Luhansk and Donetsk -- both about 60 miles from the crash site -- and widened the area they have under their control, the Defense Ministry said in a statement on its website.